ceiling junction boxes

hi 2 all,
I know this is alot, but...is it ok to bury junction boxes in the attic space with insulation?
How many outlets can i run from one 15a tripper in the breaker box?
Should i use 12/2 for all the power and 14/2 for the switches?
How far between clamps when running steel-wrapped cable in crawl space?
Can i mount junction boxes on ceiling joists?
What is cable staple spacing when running 12/2 or 14/2 along ceiling joists and wall studs?
thanks!

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I know this is alot, but...is it ok to bury junction boxes in the attic space with insulation? No, they should be readily accessible and in sight.
How many outlets can i run from one 15a tripper in the breaker box? As many as you want according this forum however, I like to use the method for load calculations, which will put that number at 10.
Should i use 12/2 for all the power and 14/2 for the switches? You can use either.
How far between clamps when running steel-wrapped cable in crawl space? MC cable needs to be strapped within every 6' of horizontal and vertical runs and within 12" of a box, fitting, etc. If they run through bored holes, this counts as support.
Can i mount junction boxes on ceiling joists? Yes
What is cable staple spacing when running 12/2 or 14/2 along ceiling joists and wall studs? Runs need to be within every4 1/2 feet of horizontal and vertical runs and within 12" of every box, fitting, etc.

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hi wirenut, tnkx for the fast reply. wow, i thought it was INCHES, not feet for cable staple spacing.... my nec2005 is sorta confusing there. in our new dining room addition, i wanted steelwrapped wire for the crawlspace for rodent protection, and as i read it, i need to use steel outlet boxes and clamps, but do i need to seal the holes in the wood where i pass the 1/2" wrap of wires with a particular sealer or bushing type plug to pass code? this inspector is...... well, you know...
tnkx again!

do i need to seal the holes in the wood where i pass the 1/2" wrap of wires with a particular sealer or bushing type plug to pass code? No. Not sure about your inspector, but where you pass through the top or bottom plate, you should use some foam insulation or equivalent to seal holes to stop air flow from these points, ie., smoke. If you run in the attic, I'd keep it as far to the outside edges as possible so when someone puts plywood up there the don't put it on top of the wire or junction boxes. I'm going by 05 code, don't have a clue about 08 but i'm sure if it's different someone will chime in.

Anti-short bushings are red plastic bushings that should've been attached to your roll of MC that, after you cut the metal, you slip this bushing in the end to keep it from cutting into the wire insulation. Yes, ground all metal boxes. As far as the GFCI's, unless you're running 8 circuits you shouldn't need all those. You can put the gfci first in line with the circuits and feed on the line side and use regular duplex recepts and feed those off the load side of the gfi.

hmmm... no red plastic bushings here, guess i'll use 12/2 romex and just rewire this whole mess, THEN i can use plastic outlet boxes too?
i just got a good deal on these gfics and like the added protection and convenience, so it IS ok to use them all around the new dining room?
tnkx again for your time and patience

hmmm... no red plastic bushings here, guess i'll use 12/2 romex and just rewire this whole mess, THEN i can use plastic outlet boxes too? yes
i just got a good deal on these gfics and like the added protection and convenience, so it IS ok to use them all around the new dining room? yes